Pump device

ABSTRACT

Pump device comprising a pump insert, without a dedicated housing, and a receiving part, wherein the pump insert is inserted in the receiving part, wherein in the receiving part the suction passage for the pump insert is designed for sucking in a fluid, wherein in the suction passage provision is made for an insertion part for optimizing fluid guiding.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No. PCT/EP2016/058010, filed Apr. 12, 2016, which claims priority to DE102015206684.3 filed Apr. 14, 2015. The entire disclosures of each of the above applications are incorporated herein by reference.

FIELD OF THE INVENTION

Pump device comprising a pump insert without a dedicated housing, wherein the pump insert is inserted into a receiving part.

BACKGROUND OF THE INVENTION

This section provides information related to the present disclosure which is not necessarily prior art.

A pump insert without a dedicated housing is known from DE102011055020A1. Such pump inserts, also called cartridge pumps, are for example inserted into transmission casings. The insert is described but the suction passage itself is not shown.

A pump, which has an insertion part in the inlet for sound attenuation, is known from DE 102013205622 A1.

A cast hydraulic unit, which has a filter insert in the suction region inside the pump, is known from DE 4334228 A1.

The suction passage for sucking in a desired fluid for such pump inserts is produced in the transmission casing, usually by metal cutting. The production by metal cutting is relatively cost intensive, however. Therefore, a solution is sought, in which solution a cost effective production and at the same time an optimized fluid flow guiding in the suction passage can be realized.

SUMMARY OF THE INVENTION

This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

It is an object of the invention to provide a pump device in which the suction passage can be produced cost effectively, and wherein an optimized fluid flow guiding can be realized.

The achieving of the object is effected by means of a pump device comprising a pump insert without a dedicated housing, wherein the pump insert is inserted into a receiving part, wherein in the receiving part the suction passage for the pump insert is designed for sucking in a fluid, wherein in the suction passage provision is made for an insertion part for optimizing fluid guiding.

Understood by pump insert according to the invention is a device which in the main contains the components of a pump, but is designed for inserting into a receiving part, for example a casing, wherein the receiving part provides a suction passage for sucking a fluid into a chamber which is formed by the pump insert and the receiving part. Such pump inserts are also referred to as cartridge pumps or cassette pumps. The pump insert, the receiving part and the insertion part can be provided by different manufacturers, wherein the pump insert and the insertion part are advantageously built in at the manufacturers of the receiving part.

As a result of the insertion part, it is possible to provide in a receiving part in a simple and cost effective manner a suction passage, the geometry of which does not have to be designed in a flow-optimized manner, but as a result of which the fluid could not ideally flow without the insertion part and for example would be prone to foaming, which would negatively influence the service life of such a pump device.

Developments of the invention are disclosed in the dependent claims, in the description and also in the attached drawings.

In a preferred embodiment, the receiving part forms the receptacle for intake of a fluid.

The receiving part can in this case preferably be a transmission casing. The interior space of the transmission casing forms the receptacle for the fluid, for example for oil. The pump insert is inserted in a transmission casing wall, wherein a suction passage for sucking in the fluid from the receptacle is formed in the transmission casing wall.

In a preferred embodiment, the suction passage is produced without metal cutting.

The suction passage is for example cast along with the casting of the receiving part. Since when forming the core or slider the passage geometry has a significant influence, the suction passage cannot be optimally designed for sucking in the fluid.

As a result of the thus non-optimized geometry of the suction passage and on account of the fact that foamed fluid at high rotational speeds can lead to cavitation in the pump device, according to the invention an insertion part is inserted into the suction passage. In this case, the suction passage, preferably in the region of the suction opening of the pump insert, is enlarged, especially preferably by metal cutting, as a result of which the insertion part can be inserted in this region in a simple manner.

This region is preferably produced by metal cutting since the geometry of the receiving part, for example the wall thickness of the receiving part, in this region does not usually allow a removal of the casting mold. If the wall thickness of the receiving part is sufficiently thick in order to enable removal of the casting mold, this region can also be formed by casting.

In one embodiment according to the invention, the insertion part is produced from plastic.

The insertion part is in this case preferably produced in an injection molding process.

The injection molding process allows a cost effective production of complex geometries.

In one preferred embodiment, the pump device, and therefore the pump insert, is designed as vane cell pump.

The vane cell pump, and therefore the pump insert, basically comprises a rotor with one vane, or a multiplicity of vanes, which is/are arranged in slots of the rotor, and also comprises a contour ring, wherein the rotor is arranged on a drive shaft in a captively retained, for example by means of a spring ring, and rotation-resistant manner. Arranged on the drive shaft are a first pressure plate and a second pressure plate, wherein the rotor, the at least one vane and the contour ring are arranged between the pressure plates.

Alternatively to the vane cell pump, the pump insert can be designed for example as a gear pump.

The pump insert is fitted in a blind hole of the receiving part. In order to hold the pump insert in position, a cover is fastened onto the receiving part, wherein the cover presses the pump insert against the wall of the receiving part and holds it in position.

The pump insert has at least two spaced apart seals, wherein the seals are preferably designed as O-rings.

In one preferred embodiment, one seal is provided on the first pressure plate and the second seal is provided on the second pressure plate, wherein the seal on the first pressure plate seals the suction chamber against the pressure chamber and the seal of the second pressure plate seals against the cover in order to thereby prevent a leakage.

Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

FIG. 1 shows a sectional view of a pump device as known in the prior art.

FIG. 2 shows a sectional view of a pump device according to the invention.

DESCRIPTION OF THE INVENTION

Shown in FIG. 1 is a pump device 1, as known in the prior art. The pump insert itself is not shown for a better overview and is provided for installation in section A. Located in a receiving casing, for example a transmission, is a receiving part 2 in which a suction passage 3 is provided supplying a fluid, wherein the suction passage 3 is formed by metal cutting. The forming by metal cutting and therefore the very cleanly designed and machined inner surface I of the suction passage 3 enables an optimization of the fluid flow into a pump chamber of the pump insert, as a result of which sucking in of air is reduced or prevented. An injector 5 is arranged in the suction passage 3.

FIG. 2 shows a pump device 1 according to the invention in a casing, which provides a receiving part 2, formed by a sub-assembly, wherein the pump device is again shown without the pump insert. The suction passage 3 is cast in the receiving part 2 along with it. The casting process of such a casing part is significantly more cost effective, but the inner surface I is significantly rougher than in the case of production by a metal cutting method. If a transmission casing is assumed, it is advisable to already design an oil reservoir as the receptacle B during the casting.

The fluid flow would turbulently makes its way to the pump without further measures.

In order to be able to optimize the fluid flow and to design the inflow to the pump in a controlled manner, an insertion part 4, which improves the fluid flow, is inserted into the suction passage 3.

The insertion part has the shape of a funnel which from an outside diameter AD, which corresponds to the inside diameter I of the suction passage, widens to a diameter D of the housing A. The insert in the suction passage 3 is cylindrical and extends into the suction passage 3 up to a depth T. This embodiment is by way of example. The insertion part can also have the shape of a cylinder which terminates in a truncated manner in the section A, or has a cylindrical shape which is widened in an optional way, wherein the diameter D does not have to be achieved for the widening.

In a preferred embodiment variant, the fluid flow in the insertion part 4 can be split into at least two inflows by partitions being provided.

The insertion part 4 according to the invention consists of plastic and is preferably produced in an injection molding process. With this, more complex insertion parts with a plurality of structured suction passage sections are also possible.

In a further preferred embodiment, provision can be made between the insertion part 4 and the suction passage 3 for an encircling seal (not shown), for example at least one O-ring or a sealing lip injected on the insertion part 4.

If required, an injector 5 (not shown) can also be inserted in the suction passage 3.

The installation of the insertion part is carried out by the insertion part being pressed into the part of the suction passage which is open toward the section A. In an optimum case, the cast structure of the suction passage is adequate in order to securely guide and to fasten the insertion part. If necessary, however, the suction passage still has to be aftermachined so that for example a cylindrical—at least in certain sections—insertion part 3 can easily be inserted.

LIST OF DESIGNATIONS

1 Pump device

2 Receiving part

3 Suction passage

4 Insertion part

5 Injector

A Section

D Diameter

I Inside diameter

AD Outside diameter

T Depth

B Receptacle 

1. A pump device comprising a pump insert, without a dedicated housing, and a receiving part, wherein the pump insert is inserted into the receiving part in a housing which is in fluid communication with a suction passage of the pump insert for sucking in a fluid, wherein the receiving part the suction passage is produced without metal cutting, wherein in the suction passage provision is made at least partially for an insertion part for optimizing fluid guiding, which has the shape of a funnel which from an outside diameter, which corresponds to the inside diameter of the suction passage, widens to a diameter of the housing.
 2. The pump device as claimed in claim 1, wherein the receiving part forms a receptacle for intake of a fluid.
 3. The pump device as claimed in claim 1, wherein the receiving part is a transmission casing.
 4. The pump device as claimed in claim 1, wherein the insertion part is produced from plastic.
 5. The pump device as claimed in claim 1, wherein the insertion part is produced in a plastic injection molding process.
 6. The pump device as claimed in claim 1, wherein the pump device is designed as a vane cell pump or gear pump.
 7. The pump device as claimed in claim 1, wherein the pump insert has at least two spaced apart radial seals for sealing against the receiving part. 